A friend of mine is going to study in the US, but will enter 2-3 months in advance to explore his new home and prepare for things. Therefore he is planning to get a B2 "prospective student" visa and then change Status to F1 before he starts school.
I'm aware that the USCIS doesn't issue visa stickers.
Therefore my question is:
If the person takes a short trip to Canada or Latin America whilst in School (i.e. after having switched to F1 Status), how can he re-enter the US?
(my understanding is that re-entering after a trip of max 30 days to Canada or Mexico is completely painless, but what about if he were to go somewhere else, such as to Brazil for a week?)